If data collection is enabled, the Glean SDKs provide a set of built-in pings that are assembled out of the box without any developer intervention. The following is a list of these built-in pings:
baselineping: A small ping sent every time the application goes to foreground and background. Going to foreground also includes when the application starts.
deletion-requestping: Sent when the user disables telemetry in order to request a deletion of their data.
eventsping: The default ping for events. Sent every time the application goes to background or a certain number of events is reached.
metricsping: The default ping for metrics. Sent approximately daily.
Applications can also define and send their own custom pings when the schedules of these pings is not suitable.
There is also a high-level overview of how the
baseline pings relate and the timings they record.
These docs refer to application 'foreground' and 'background' state in several places.
For Android, this specifically means the activity becomes visible to the user, it has entered the
Started state, and the system invokes the
This specifically means when the activity is no longer visible to the user, it has entered the
Stopped state, and the system invokes the
This may occur, if the user uses
Overview button to change to another app, the user presses the
Back button and
navigates to a previous application or the home screen, or if the user presses the
Home button to return to the
home screen. This can also occur if the user navigates away from the application through some notification or
The system may also call
onStop() when the activity has finished running, and is about to be terminated.
For iOS, the Glean Swift SDK attaches to the
This notification is posted by the OS shortly before an app leaves the background state on its way to becoming the active app.
For iOS, this specifically means when the app is no longer visible to the user, or when the
This may occur if the user opens the task switcher to change to another app, or if the user presses the
to show the home screen. This can also occur if the user navigates away from the app through a notification or other
Note: Glean does not currently support Scene based lifecycle events that were introduced in iOS 13.